Reply to «Percutaneous bone biopsy is different to the probe to bone test». Comments on «Diabetic foot osteomyelitis: Is conservative treatment possible?»

Dear Editor,

Thank you for the comments made in response to our manuscript on “Diabetic foot osteomyelitis: Is conservative treatment possible?”.¹

Effectively, and as you have correctly deduced from the manuscript, the technique used to diagnose episodes of osteomyelitis was per-wound bone biopsy, after cleaning and debriding the ulcer. This technique may lead to false positive results, even when using measures to minimise contamination. However, it is the technique considered most appropriate at the time, taking into account the fact that half of the episodes were seen on an outpatient basis and this technique has been used before by other working groups with similar results.²

With regard to bone culture-guided antibiotic therapy, we used unguided antibiotic therapy in those cases where not all microorganisms were covered or when the duration of treatment was shorter than usual (e.g. in the case of non-fermenting gram-negative bacilli requiring intravenous treatment).

Differences between the groups in terms of the percentage of patients receiving bone culture-guided antibiotic therapy resulted in OR of 0.2 in the multivariate analysis. This result, although not significant, may suggest that, if a larger study sample had been used, this variable may have shown a link.

Nevertheless, as we have already commented in the last paragraph of the Results section and highlighted in the Discussion section, the only factor that was significantly associated with conservative treatment failure in our study was ulcer size >2 cm.